JPH1089565A - Pipe joint - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent slip-off and rotation of a pipe with a simple structure by arranging an opening on an expansion part formed matching with the tangent direction of a hollow hole, in a device formed by inserting a shear key from the opening arranged on one side of a circumferential rim of an annular groove part of an external cylinder, into the hollow hole sectioned by the annular groove part. SOLUTION: An annular groove part for housing a sealing member 1 is arranged in an external cylinder 2, and also an annular groove part 8 for forming the half of the outside of a hollow hole for housing a rod shaped shear key 4 therein. An annular groove part 9 which is engaged with the annular groove part 8 of the external cylinder 2 after inserting and for forming the half of the inside of the hollow hole, is formed outside an inner cylinder 3, and the external cylinder 2 and the inner cylinder 3 are inserted and engaged with each other. One part of the annular groove part 8 of the external cylinder 2 is expanded outward, and an inserting inlet 15 for inserting the shear key 4 drilled on a position extended from a center tangent line of the hollow hole is arranged on the end part thereof. The shear key 4 is mounted from the tangent direction of the hollow hole along the hollow hole for at least 1/2 circumference or more, more preferably for along from 3/4 to nearly 1 circumference, serving the inserting inlet 15 as a guide.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention mainly relates to sanitary and air-conditioning piping of building equipment, in which thin pipes can be easily connected and detached when connecting thin pipes, rotation of the connected pipes can be prevented, and positioning in the longitudinal direction can be performed. It is about the pipe joint to be secured.

[0002]

2. Description of the Related Art Conventionally, when connecting relatively thin-walled pipes used for various equipment piping (for example, stainless steel pipes for general piping, so-called thin-walled stainless steel pipes, various copper pipes, resin pipes, etc.), mechanical joints are used. Although various types of pipe joints have been proposed, few of them have a simple structure with a small number of parts and are provided with a reliable stopper and detent means.

[0003] In recent years, it has been said that, in various piping for air conditioning and sanitation of building equipment, construction work for attaching heat insulating material to most of the piping for the purpose of keeping heat and cooling and preventing dew condensation has been performed. As shown in FIG. 17, the outer diameter a of the conventional lock nut type pipe joint 19 is much larger than the outer diameter b of the pipe 20 because the outer diameter a of the conventional lock nut type pipe joint 19 is large. Therefore, the installation of the heat insulating material 21 at the joint portion cannot be performed continuously with the pipe portion, and this has been a factor of increasing the heat insulating work cost.

In some cases, the outer diameter of the large-diameter lock nut type pipe joint 19 cannot penetrate a sleeve (a guide cylinder of a pipe penetrating portion such as a beam, a wall, or a floor slab). It was inconvenient for plumbing.

[0005]

However, the above-mentioned prior art has the following problems. That is, a pipe joint that uses a lock nut or is fixed by a housing requires a tool for turning a nut or a bolt, and the tightening and tightening of screws is often performed with the sense of an operator. Since it is extremely difficult to control with the tightening torque of, construction work with stable quality cannot be performed.

[0006] In addition, screw tightening work in the construction work of piping members including screw connection for pipes is a considerable amount of labor, and there is a lot of work at high places. In addition to the above, there is a demand for "simplification" and "labor saving" of plumbing work which eliminates such heavy work and sensory work.

In recent years, the importance of renewal of facilities (renewal work) has increased, and the specifications required for pipe joints are that they can be easily disassembled at the time of renewal. There is a need for a tube connection configuration that addresses this problem.

There are various plug-in configurations using a sealing member such as an O-ring for connecting the pipe and the pipe joint. However, the advantage is that the fitting between the cylinders is rotatable, but a valve is provided in the middle of the pipe. When a bypass set is assembled, they may unexpectedly rotate, which is extremely inconvenient when a situation such as tilting of a valve occurs. Therefore, it is necessary to provide a simple "rotation stop mechanism" from the viewpoint of preventing rotation of the pipe and the pipe joint.

In general, in a mechanical type pipe joint for connecting a thin pipe, an outer diameter of the pipe and the joint except for a caulking type pipe joint (however, in general, a caulking type pipe joint has a disadvantage that it cannot be easily disassembled). Due to the large steps in the dimensions, it is necessary to perform insulation work separately for pipes and pipe joints in the installation work of heat insulating material, which is extremely inefficient in construction work and it is not possible to penetrate the hole of the sleeve. It is inconvenient in itself, and eventually requires a compact pipe joint without a large step in the outer diameter of the pipe.

[0010] In piping for building equipment, there is a need for a reliable "confirmation means" for connection and fixing of pipes for preventing pipes from coming off, such as preventing mistakes in pipe construction and avoiding pork.

[0011]

[Object] The present invention has been proposed in view of the aforementioned disadvantages,
Its purpose is to mainly prevent the pipe from falling off and prevent rotation with a simple structure at the pipe joint connecting thin-walled pipes, while having a compact outer diameter shape compared to the outer diameter of the pipe. Is intended to be provided.

[0012]

In order to achieve the above object, a pipe joint according to the present invention has a pair of an outer cylinder 2 and an inner cylinder 3 which are engaged with each other via a sealing member 1 in a longitudinally overlapping manner. A hole 5 for accommodating a flexible rod-shaped shear key 4 is provided at a position where the inner peripheral edge 6 of the outer cylinder 2 and the outer peripheral edge 7 of the inner cylinder 3 face each other under engagement. The shear key 4 is formed by a pair of annular grooves 8 and 9, and the shear key 4 can be inserted from the outside into an opening provided at a part of the peripheral edge of the annular groove 8 of the outer cylinder 2. Shear key 4
In a connection configuration of a pipe containing at least one half of the hole, the first opening is formed as an insertion port 15 provided in a bulge 18 formed in conformity with the tangential direction of the hole 5.
The outer periphery of the distal end portion of the inner cylinder 3 which is in close contact with the sealing member 1 is formed into a polygon-formed portion 12, and the intermediate portion of the outer cylinder 2 is engaged with the polygon-formed portion 12 of the inner tube 3. The outer cylinder 2 and the inner cylinder 3
A second feature is that a detent is formed in the axial rotation direction between the outer cylinder and the outer cylinder. 2 is formed into a polygon forming part 14 which engages with the polygon forming part 12 of the inner cylinder 3, and the polygon reducing base w of the inner cylinder 3 is attached to the polygon reducing base w of the outer cylinder 2. The third feature is that the z is locked and the positioning in the longitudinal direction is configured, and a display portion 16 capable of confirming the mounting of the shearing key 4 is provided at the insertion side h of the shearing key 4. 4 and features
A fifth feature is that a screw locking member 17 for locking to the insertion opening 15 is provided on the insertion hand side h of the shearing key 4, and the shearing key 4 is formed by a close contact coil spring, and When the outer diameter is formed slightly larger than the inner diameter of the hole 5 and the insertion end side k is pulled, the outer diameter of the dedicated key 4 itself is reduced and enters the hole 5 to complete the mounting. When the pulling is stopped, the outer diameter of the close contact coil spring 4 expands and returns, filling the hole 5 and pressing the inner wall of the hole 5 to prevent the shear key 4 from loosening and coming off. This is the sixth feature.

[0013]

In the present invention employing the above-described structure, the following operation is exhibited. Explaining that the outer cylinder corresponds to the pipe joint and the inner cylinder corresponds to the pipe, a groove for accommodating a self-sealing sealing member such as an O-ring is provided inside the outer cylinder (pipe joint) to accommodate the sealing member. An annular groove forming an outer half of a hole for accommodating a flexible rod-shaped shear key, and an outer groove of the hole engaged with the groove of the outer cylinder after being inserted into the groove of the outer cylinder outside the inner cylinder (tube). An annular groove forming an inner half is provided, the outer cylinder and the inner cylinder are inserted and locked, and an insertion opening of the shear key is formed at a tangential position reaching the center of the hole from outside the outer cylinder. If the shearing key is inserted along the hole formed on the periphery from the insertion port, a flexible rod-shaped shearing key is curved along the annular hole. And proceed for at least 1/2 round (approximately 3/4 round). It is attached to. The inner diameter of the hole is slightly larger than the outer diameter of the shearing key, and the shearing key can be freely moved in the hole, and the inner cylinder and the outer cylinder can be removed by the shearing key filled and mounted in the hole. It has a preventive action.

The end of the portion where the outer peripheral portion of the inner cylinder is in close contact with the sealing member is reduced in diameter into a polygonal shape, and at least a part of the position of the outer cylinder which engages with the distal end of the inner cylinder is defined as the outer peripheral portion of the inner cylinder. Molded to form one surface of the polygon with which the tip engages,
If the inner cylinder and the outer cylinder are fitted at an appropriate rotation angle, it is possible to constitute a detent of the pipe joint. In addition, the rotation angle at the time of insertion between the inner cylinder and the outer cylinder is rotated in accordance with the angle of one surface of the polygon, so that a member having directionality in a pipe posture such as a valve or a tee and a swing angle of the pipe are set. Available to

The positioning in the longitudinal direction can be performed only by locking the polygonal reduced diameter portions of the cylinders to each other, and the semicircular annular grooves of the cylinders to be engaged under the overlap easily face each other to form a circular hollow. The formation of the holes facilitates insertion of the shear key.

If an indicator (display function member) indicating that the shear key is securely mounted is provided near the insertion side of the shear key, it is possible to confirm the mounting of the shear key from a distance.

The locking of the shearing key can be achieved by providing a means for inserting the shearing key, which is inserted into the insertion opening of the outer cylinder bulging portion, at the insertion side slightly larger than the diameter of the hole of the insertion opening and engaging it. (Prevention of detachment) is ensured, and safety is ensured by preventing detachment during piping vibration and earthquakes.

Further, the shearing key is formed by a close contact coil spring, the outer diameter of which is set slightly larger than the inner diameter of the hole. There is no filling, close contact and loosening. There is no need for the insertion port of the bulging portion of the outer cylinder or the locking means of the shearing key, which is simple and convenient.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment according to the present invention will be described with reference to FIGS. 1 to 13, in which an outer cylinder corresponds to a pipe joint and an inner cylinder corresponds to a pipe. First, in FIGS. 2 and 3 of the first embodiment,
An annular groove for accommodating the sealing member 1 (O-ring) is provided on the inner side of the outer cylinder 2 to provide airtightness with the inserted inner cylinder 3 and to accommodate a rod-shaped shear key 4 having flexibility. 5 and an annular groove 8 forming the outer half of each.
On the outer side of the inner cylinder 3, there is provided an annular groove 9 which forms the inner half of the hole 5 to be engaged after being inserted into the annular groove 8 of the outer cylinder 2, and the outer cylinder 2 and the inner cylinder 3 are inserted and engaged. Let it.

In FIGS. 1 and 4 of the first embodiment, a part of the outer cylindrical annular groove 8 constituting the hole 5 is formed to bulge outward, and the center of the hole 5 is extended at the end thereof. An insertion port 15 for inserting the shearing key 4 pierced thereon is provided.
When the shear key 4 is inserted with the guide as a guide, the mounting of the shear key 4 becomes easier and convenient. When the shearing key 4 is inserted from the insertion opening 15 and is advanced along the annular hole 5 formed on the peripheral edge, the rod-shaped shearing key 4 having flexibility is curved along the hole 5. And go at least 1 /
It is mounted as shown in FIG. 4 over two or more rounds, generally from 3/4 to almost one round.

The inner diameter of the hole 5 is formed slightly larger than the outer diameter of the shear key 4, and the shear key 4 can move and bend within the hole 5, and is mounted in the hole 5. The shear key 4 acts as a shearing resistor for the longitudinal movement between the outer cylinder 2 and the inner cylinder 3, thereby preventing the longitudinal movement between the inner cylinder 3 and the outer cylinder 2. The shearing key 4 to be inserted advances and retreats along the outer peripheral groove of the hole 5 by bending (there may be a mode of rotation and bending depending on the method of mounting the shearing key described later with reference to FIG. 15). It is required that the material has
In addition to flexible materials such as resin and elastic stainless metal, stainless steel close-contact coil springs and the like are suitable because of their high shear strength.

When disassembling the pipe joint, the pipe joint can be easily removed by performing the above-described reverse working steps. The insertion hand side h of the shearing key 4 exposed from the hole 5 of the insertion opening 15 is partially exposed as shown in FIG.
The shearing key 4 can be easily removed by pulling it out with a general-purpose tool such as pliers or pliers or by hand. In particular, if the shearing key 4 is a close contact coil spring, if the insertion side h of the shearing key 4 is grasped and pulled, the outer diameter of the shearing key 4 itself is reduced to facilitate removal.

In the embodiment of the present invention, the annular groove for mounting the O-ring-shaped sealing member 1 is a "V-shaped groove" in consideration of moldability of hydraulic bulging of a cylindrical material, as shown in FIG. Of course, a "rectangular groove" may be used. Further, in the embodiment of the present invention, an O-ring is shown as the sealing member 1, but it goes without saying that various members such as a self-sealing sealing member such as a Y-ring, a U-packing, and an X-ring can be applied.

Next, a second embodiment of the present invention in which the joint connection portion is prevented from rotating in the axial direction will be described with reference to FIGS. In FIG. 1 of the first embodiment, since the annular groove 9 forming the hole 5 has a continuous groove shape on the peripheral edge of the inner cylinder 3, the inner cylinder 3 and the outer cylinder 2 can be connected even after the shearing key 4 is mounted. Is free to rotate. Generally, the connection between the pipe and the pipe joint can be made freely even in a freely rotatable state. However, a member having a vertical orientation in the mounting position, such as a valve or a meter, is provided in an intermediate route of the pipe, or a pipe joint portion of the bypass circuit ( The free rotation of the tee) may cause inconvenience by tilting the members and the bypass circuit.

Therefore, as shown in FIG. 7, a cylindrical sliding portion whose outer peripheral portion is deviated from the portion where the outer peripheral portion of the inner cylinder 3 is in close contact with the sealing member 1 is reduced in diameter to a polygonal forming portion 12, and the outer cylinder is formed. At least a part of the intermediate portion of the inner cylinder 3 engaging with the polygon forming portion 12 is formed into a flat shape 14 'with which the inner cylinder polygon forming portion 12 engages (FIG. 8 shows the polygon 14, FIG. 9 is a dihedral shape 14 '), the inner cylinder 3 and the outer cylinder 2 are
If the fitting is inserted and inserted until the angle of (14, 14 ') is adjusted and locked, rotation of the pipe joint outside the longitudinal direction can be prevented, and the inner diameter of the polygonal reduced-diameter inner base W of the outer cylinder 2 can be reduced. The arcuate outer diameter base portion Z of the cylinder 3 is locked and serves as positioning means in the longitudinal direction of the two cylinders, so that the annular groove portion 8 of the connected outer cylinder 2 and the annular groove portion 9 of the inner cylinder 3 coincide with each other. The hole 5 is formed, and the inner cylinder 3 and the outer cylinder 2 fitted by inserting the shear key 4 into the hole 5 from the insertion port 15 are prevented from coming off and connected.

As is well known, 90 ° and 45 ° elbows are commercially available for various types of pipe joints, and the bending direction of the equipment pipe can be generally covered by the above two types.
Therefore, it is preferable that the molded polygon provided on the pipe joint and the pipe of the present invention is a regular octagon which can be fixed by 45-degree rotation as shown in FIGS. 6 to 9 and FIG. It is preferable that the outer cylinder has a two-sided shape as shown in FIG.

Next, FIG. 10 shows a third embodiment of the present invention in which the outer cylinder 2 is used as a socket (pipe joint) and pipes (inner cylinder 3) are connected to both ends. FIG. 11 shows an embodiment in which both means for rotation prevention and longitudinal positioning are employed.

A fourth embodiment of the shear key according to the present invention will be described with reference to FIGS.
In the pipe joint configuration according to the present invention, whether or not the shearing key 4 is attached is extremely important as a pipe retaining structure. Therefore, it is important to confirm the mounting of the shear key in the construction work and to ensure that the shear key 4 after mounting is not relieved by vibration or the like. Therefore, as shown in FIG. 12, a display section 16 (indicator mechanism based on color, shape, or the like) that indicates that the shearing key 4 is securely mounted is provided at the insertion hand side h of the shearing key 4, so that it can be viewed from a distance. The user can easily confirm the mounting of the shearing key 4.

Further, as shown in FIG. 13 and FIG. 14, the outer diameter of the insertion hand side of the shearing key 4 to be inserted into the insertion port 15 provided in the outer cylinder 2 is slightly smaller than the inner diameter of the insertion port 15. The shearing key formed by a close contact coil spring as shown in FIG. 15 is also rotatable, so that a screw s is provided in the insertion port 15 to insert the shearing key 4 near the insertion side h. Butterfly bolt 17 connected and integrated with the part
If a means such as screwing is used to lock the shear key, it is ensured that the shear key 4 is attached and that the shear key is securely prevented from coming off, which is safe against vibration of the piping and earthquake.

Although the connection structure of the pipe according to the present invention has been mainly described as the relation between the pipe and the pipe joint (socket), it is also applied to the connection between the pipe and the pipe as well as the pipe joint other than the pipe and the socket. Needless to say, this is possible.

The O-ring-shaped sealing member 1 provided on the outer cylinder 2 side shown in FIG. 16 can be mounted on the inner cylinder 3 side. However, in this case, the inner diameter of the pipe is reduced, which is not preferable. It should be noted that the sealing member 1 may be functionally provided as a single unit as shown in FIG. 16, and that the two sealing members 1 shown in the embodiment of the other figure are mounted to ensure fluid sealing reliability and safety. It is a configuration intended for sex.

FIGS. 17 and 18 are front cross-sectional views each showing an embodiment in which insulation work is performed on a pipe joint. FIG. 17 shows an example of heat insulation work on a pipe joint using a conventional lock nut. FIG. 18 shows an embodiment of heat insulation work for a pipe joint according to the present invention.

[0033]

According to the present invention, the following specific effects can be obtained. It eliminates the need for tools that rotate nuts and bolts in pipe joints that use a conventional lock nut or that is fixed with a housing, and provides stable quality because there is no sensation, such as screw tightening, and no hard work. Construction work is possible. In addition, it is lightweight and compact, and is effective for work at high places, simplification of work, and labor saving.

Since the number of parts is extremely small, it can be easily disassembled at the time of renewal work of equipment piping, and the material after disassembly can be easily separated, which contributes to recycling of waste materials.

Since a "rotation preventing mechanism" for preventing rotation of the pipe and the pipe joint with a simple configuration is provided, there is no possibility of unexpected rotation of the pipe or the pipe joint. Since it also serves as a directional positioning means, a hole can be easily formed, which is convenient for inserting a shear key.

The outer diameter of the pipe joint is not significantly different from the outer diameter of the pipe, and the pipe and the pipe joint can be continuously heat-insulated in the heat insulating material installation work. Since the pipe joint can penetrate the sleeve, the efficiency of construction work is extremely high.

Since the presence or absence of the shear key can be easily checked from the outside of the piping system, it is possible to completely prevent the pipe from deviating, and it is also appropriate to take measures to prevent the shear key from coming off.

[Brief description of the drawings]

FIG. 1 is a front upper half sectional view of a pipe joint according to a first embodiment of the present invention (in a state where a shearing key is completely mounted).

FIG. 2 is a front upper half sectional view showing a state before connection of the pipe joint according to the first embodiment.

FIG. 3 is a front upper half cross-sectional view showing a state after pipe insertion and connection of the above pipe joint (the shear key is not mounted).

FIG. 4 is a sectional view taken along line IV-IV of FIG. 1;

FIG. 5 is a front external view of FIG. 1;

FIG. 6 is a projection (longitudinal direction positioning means) on the inner cylinder side of the above.
FIG. 5 is a front upper half sectional view showing a mode in which a concave portion is set on the outer cylinder side.

FIG. 7 is a front upper half sectional view of a pipe joint according to a second embodiment of the present invention.

FIG. 8 is a sectional view taken along line VIII-VIII of FIG. 7;

FIG. 9 is a cross-sectional view showing another embodiment different from FIG.

FIG. 10 is a front upper half sectional view of a pipe joint according to a third embodiment of the present invention.

FIG. 11 is a front upper half sectional view showing a state in which the middle part of the outer cylinder and the tip part of the inner cylinder are formed into a polygon and inserted and connected together in the pipe joint.

FIG. 12 is a sectional view showing another embodiment of the shearing key of the pipe joint of the first to third embodiments of the present invention and the insertion port thereof, which is different from FIG. 4;

FIG. 13 is a sectional view showing another embodiment of the above.

FIG. 14 is a sectional view showing still another embodiment of the above.

FIG. 15 is a sectional view showing still another embodiment of the above.

FIG. 16 is a cross-sectional view showing a state in which a shear key of the pipe joint according to the present invention is inserted and connected.

FIG. 17 is an external view showing an embodiment of a shear key according to the embodiment.

FIG. 18 is an external view showing another embodiment of the above.

FIG. 19 is an external view showing still another embodiment of the above.

20 is an external view showing an embodiment of the elastic cord for pulling the shear key of FIG. 19;

FIG. 21 is a front upper half sectional view showing an embodiment in which a sealing member provided on the outer cylinder side is set on the inner cylinder side.

FIG. 22 is a front sectional view showing an embodiment in which heat insulation work is performed on a conventional lock nut type pipe joint.

FIG. 23 is a front sectional view showing an embodiment in which thermal insulation work is performed on the pipe joint according to the present invention of FIG. 10;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Sealing member 2 Outer cylinder 3 Inner cylinder 4 Shear key 5 Void 6 Inner peripheral part of outer cylinder 7 Outer peripheral part of inner cylinder 8 Annular groove part of outer cylinder 9 Annular groove part of inner cylinder 10 Convex part (positioning means) 10 ′ Concave portion (positioning means) 11 Outer end outer periphery of inner cylinder 12 Polygonal forming part of inner cylinder 13 Middle part of outer cylinder 14 Polygon forming part of outer cylinder 14 'Flat forming part of outer cylinder 15 Insertion port 16 Display part 17 Threaded locking member 18 Rise 19 Conventional lock nut type pipe joint 20 Conventional lock nut type pipe 21, 21 'Insulation material a Outer diameter dimension of conventional lock nut type pipe joint b Outer diameter dimension of the same pipe c Opening mouth d Outer diameter of pipe joint of the present invention e Insertion hand side stopper f Hook (shear key) f 'Hook (single cord) g Pull cord g' Pull cord (single) h Insertion hand side k Insertion tip side s Polygonal reduced-diameter base of the w barrel of polygonal reduced-diameter base z inner cylinder

Claims (6)

[Claims] 1. An air hole (5) having a pair of outer cylinders (2) and inner cylinders (3) engaged with each other in a longitudinal direction through a sealing member (1) in an overlapping manner, and accommodating a flexible rod-shaped shearing key (4). A pair of annular grooves 8 provided at positions where the inner peripheral edge 6 of the outer cylinder 2 and the outer peripheral edge 7 of the inner cylinder 3 face each other under engagement.
9, the shear key 4 can be inserted from the outside into an opening provided in a part of the peripheral edge of the annular groove 8 of the outer cylinder 2, and the shear key 4 A pipe joint characterized in that, in a connection configuration of pipes housed over more than two rounds, the opening is an insertion port 15 provided in a bulged portion 18 formed so as to match a tangential direction of the hole 5. 2. An outer periphery of a distal end portion of the inner cylinder 3 which is in close contact with the sealing member 1 is formed into a polygon forming portion 12, and an intermediate portion of the outer cylinder 2 is engaged with the polygon forming portion 12 of the inner cylinder 3. The pipe joint according to claim 1, wherein the fitting is formed into a polygonal-shaped portion 14 to be fitted, and a detent is formed between the outer cylinder 2 and the inner cylinder 3 in the axial rotation direction. 3. An outer periphery of a distal end portion of the inner cylinder 3 which is in close contact with the sealing member 1 is formed into a polygon forming portion 12, and an intermediate portion of the outer cylinder 2 is formed into a polygon forming portion of the inner cylinder 3. And the polygonal reduced-diameter inner base w of the outer cylinder 2 is engaged with the polygon-reduced outer base z of the inner cylinder 3 to form a longitudinally positioned portion. The pipe joint according to claim 1 or 2, wherein: 4. The pipe joint according to claim 1, further comprising a display portion 17 provided on an insertion side h of the shearing key 4 so as to confirm the mounting of the shearing key 4. 5. The pipe joint according to claim 1, wherein a threaded locking member for locking the insertion port is provided on an insertion side h of the shearing key. 6. A hole 5 for accommodating a flexible rod-shaped shearing key 4 having a pair of an outer cylinder 2 and an inner cylinder 3 which are engaged with each other in a longitudinal direction through a sealing member 1 in an overlapping manner. A pair of annular grooves 8 provided at positions where the inner peripheral edge 6 of the outer cylinder 2 and the outer peripheral edge 7 of the inner cylinder 3 face each other under engagement.
9, the shear key 4 can be inserted from the outside into an opening provided in a part of the peripheral edge of the annular groove 8 of the outer cylinder 2, and the shear key 4 In the connection configuration of pipes housed over two turns, the shearing key 4 is formed by a close contact coil spring, the outer diameter of the coil spring is formed slightly larger than the inner diameter of the hole 5, and the insertion tip side k is The pipe joint according to claim 1, wherein the pipe joint is inserted and mounted in the hole 5 by reducing the outer diameter by pulling the pipe joint, and the pipe joint according to claim 1.